Apparatus for making molds for rings.



G. E. BURNS.

Patented May 26, 1914.

S G N I R72 01 Pm. mm 0%. MA GD u IT. HF m I u F0 I m MP A P P A In, 67'Z 2 GEORGE 'E. BUR-NS, OF CENTRAL FALLS, RHODE ISLAND.

APPARATUS FOR MAKING MOLDS FOR RINGS.

Specification of Letters Patent.

Patented May 26, 1914.

Application filed April 1, 1912. Serial No. 687,605.

To all whom it may concern:

Be it known that I, GEORGE E. BURNS, a citizen of the United States,residing at Central Falls, in the county of Providence and State ofRhode Island, have invented new and useful Improvements in Apparatus forMaking Molds for Rings, of which the following is a specification.

This invention relates to a device for making molds from which to castfinger rings.

The object of the invention is to provide a device of the character setforth in which a pattern of a half ring can be utilized to make molds,two of which are set together to form a complete mold in which can becast one or more rings. The molds as formed in the apparatus are thenbaked, two of the half molds put together and the metal poured into themto cast the rings which are then taken from the molds and finished in amanner well known to those skilled in the art.

The invention consists in the combination and arrangement of parts setforth in the following specification and particularly pointed out in theclaims thereof.

Referring to the drawings: Figure 1 is a plan view of my improvedapparatus for making molds for rings showing one of the core printformers in position with a half ring pattern applied thereto. Fig. 2 isa side elevation of the base with a core print former in positionthereon. Fig. 3 is a sectional elevation taken on line 3-3 of Fig. 1.Fig. 4 is a sectional elevation taken on line 4- 1 of Fig. 1. Fig. 5 isa perspective View of a half ring pattern. Fig. 6 is a plan of a halfmold with two ring imprints therein. Fig. 7 is a sectional elevation oftwo half molds taken on line 77 of Fig. 6 showing a core in position fora ring to be cast.

Like numerals refer to like parts throughout the several views of thedrawings.

In the drawings, 10 is a base, preferably having an inclined top 11. Theapparatus shown in the drawings is adapted to make a mold with twoprints for casting rings therein and in Fig. 1 a single core printformer is shown with a half ring pattern thereon, the other core printformer being removed for the sake of clearness in illustration.

12 is a core print. former, semi-cylindrical in shape and having pins 13projecting into its fiat side, said pins projecting from the ends and isshown as provided with a half head or crown 18 terminating at its underside adjacent'the tang 16 in a central divisional line a. It is veryimportant that the pattern 15 should be exactly midway be tween the twoends of the core print former 12, because the complete mold is made fromtwo half molds and when they are reversed it is necessary that the twosides of the mold should be exact duplicates and that they should bereversible, so that the two sides of the ring will match and make aperfect casting.

The ring pattern 15 is positioned midway of the ends of the core printformer by means of suitable accurate measuring instruments and the ringpattern is positioned cireumferentially of the former by locating thestraight central edge a of the crown in alinement with the flat underface of said former.

Base plates 19, 20, 21 and 22 are provided, the tops of which are flushwith the top of the base 10. The base plates 19 and 20 are adapted toslide in a slot 28 provided in the upper face of the base 10 and theplates 21 and 22 are slidable toward each other in a slot 24-, alsoformed in the upper face of the base 10. The base plates 19 and 21 aremoved toward the plates 20 and 22, respectively, by adjusting screws 25and 26, each of which has screw-threaded engagement with the base 10,said screws being provided with annular flanges 27 which project intocorresponding grooves 28 formed in the under side of said base plates 19and 21, so that when the screws 25 and 26 are rotated the base plates 19and 21 will be moved toward or away from the plates 20 and 22. Thesebase plates 19 and 21 are adjusted until they engage the tangs 16 and17, respectively, of the pattern 15, the pattern being located, asbefore set forth, inthe exact center between the ends of the core printformer. The base plates 20 and 22 are then moved toward the ring-patteni15 until they engage the tangs 16 and 17, respectively, on the oppositeside of said tangs from that engaged by the plates 19 and 21.

The base plates 20 and 22 are locked in position in their respectiveslots by setscrews 29 and 30, respectively, said setscrews bearingagainst friction blocks 31 and 32, respectively, which friction blocksbear againstthe plates 20 and 22, respectively. Thus the finger ringpattern is locked in position midway between the ends of the core printformer.

he space between the adjacent ends of the plates 19 and 20, outside thepattern ring, is filled by a stop plate 33 and the space between theadjacent ends of the base plates 21 and 22, outside the pattern ring, isfilled by a stop plate 34. The stop plate 33 is slidable in a slot 35and the stop plate 34- is slidable in a slot 36, both of said slots 35and 36 being in the top of the base 10. Setscrews 37 are provided forthe purpose of locking a rib 38 in position.

A runway in the mold is formed by providing a projecting rib 38 on thetop of the base and this projecting rib is connected to one side of thering pattern by a cross rib 39 projecting upwardly from the stop plate34.

A casing 40 surrounds the base 10 and its side walls 41 project upwardlyabove the upper face of the base 10, thus making an open chamber 12above the upper face of the base in which moldable material can beforced to make a half mold. The inner surfaces 4 1 of the casing 10 areinclined or tapered inwardly so that when the casing is lifted from thebase, the half mold will be lifted with it.

The general operation of the device hereinbefore specifically describedis as follows: The half ring pattern is placed upon the semi-cylindricalcore print former and by means of careful measurements, the same islocated exactly midway bet-ween the opposite ends of said core printformer and with the straight side a of the crown portion 18 thereof inalinement with the fiat face of said semi-cylindrical core print former.Said core print former is then placed in position with the pins 13projecting into the holes therein, and with the tangs projecting downinto the slots 23 and 24 in the base 10 and between the adjacent ends ofthe base plates 19, 20 and 21 and 22. The base plates 19 and 21 are thenmoved by means of the adjusting screws 25 and 26 in their respectiveslots until their inner ends engage the tangs 16 and 17 on the oppositesides of said tangs from the base plates 20 and 22. The base plates 20and 22 are then brought forward until their ends engage the tangs 16 and17 on the opposite sides of said tangs from the base plates 19 and 20.The plates 20 and 22 are then locked in position by the set-screws 29and 30 and the friction blocks 31 and 32. The stop plates 33 and 3 1 arethen moved in their slots 35 and 36 until they abut against the oppositesides of the ring pattern 15.

If it is desired to make a mold for two rings, then two of the coreprint formers, with their half ring patterns, are applied to the base10.

he casing ll) being in position, moldable material is now forced intothe chamber 1:2 and when removed will present an inner surface like thatillustrated in 6. The half mold as has a print therein adapted toreceive a core 4-? (see 6 and 7) and said half mold d3 has also theimpression 48 of the ring pattern 15 therein. The half molds, afterhaving been taken out of the apparatus for making the same, hereinbeforedescribed, are baked and then two of said half molds 43 and are placedtogether, shown in Fig. vith cores 47 resting therein in the impressionsmade by the core print formers 12. When the molds have been baked andplaced in the position illustrated in Fig. 7, the complete mold isformed and ready to have a ring cast there in, which is done by pouringthe metal in through the runway and cross runways 50, filling the spacebetwee the molds and the cores at? and thus forming two complete lingerrings. The finger rings are then taken from the molds and finished inthe usual manner.

By having the upper face of the base inclined at an angle and the baseplates and stop plates also inclined at an angle and substantially flushwith the upper face of said base, a ring pattern provided with undercutengraving on its sides may be utilized to form an imprint in the moldfrom which, by the use of two of said molds, as hereinbefore described,a ring with undercut engraving on opposite sides may be cast, but it isnot necessary that the upper face of the base should be inclined, exceptwhere it is desired to make a mold to cast rings with undercut portionsin their surfaces. Otherwise, the upper face of the base could behorizontal.

Having thus described my invention, what I claim and desire by LettersPatent to secure is:

1. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, and a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former.

2. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former and means adapted to engage said tangs and hold saidpattern positioned midway between the ends of said core print former.

3. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former and means to lock said core print former to said base.

4. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former and means adjustable on said base toward and away fromsaid ring pattern and adapted to engagesaid tangs, whereby said patternmay be held positioned midway between the ends of said former.

5. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former and a pair of base plates slidable on said base towardand away from each other, their adjacent .ends adapted to engageopposite sides, respectively, of one of said tangs.

6. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former, a pair of base plates slidable on said base towardand away from each other, their adjacent ends adapted to engage oppositesides, respectively, of one of said tangs, a screw having screw-threadedengagement with said base, and an annular flange on said screwprojecting into a corresponding groove in one of said base plates,whereby said last-named base plate may be adjusted toward and away fromsaid pattern.

7. An apparatus for making molds having, in combination, a base, asemi-cylindrical core print former mounted on said base, a half ringpattern with a tang at each end thereof, respectively, applied to saidcore print former, a pair of base plates slidable on said base towardand away from each other, their adjacent ends adapted to engage oppositesides, respectively, of one of said tan s and a stop plate slidable onsaid base and adapted to enter the space between the adjacent ends ofsaid base plates.

8. An apparatus for making molds having, in combination, a base, aplurality of semi-cylindrical core print formers mounted on said base,half ring patterns with tangs at each end thereof, respectively, appliedto said core print formers, said base having two slots in its upper faceinto which said tangs project, and a plurality of pairs of base platesin each of said slots, the members of each pair adapted to be adjustedtoward each other and to clamp one of said tangs between their adjacentends.

9. An apparatus for making molds having, in combination, a base havingan inclined upper face, a semi-cylindrical core print former mounted onsaid base, a half ring pattern with a tang at each end thereof,respectively, applied to said core print former and a verticallyarranged casing surrounding said base and open at its upper end toreceive moldable material crowded into said casing and covering saidhalf ring pattern.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

GEORGE E. BURNS.

'Witnesses:

CHARLES S. GooDINe, SYDNEY E. TAFT.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, I). C.

